Single-eccentric reversing-gear for steam-engines.



No. 841,934. PATENTED JAN. 22, 1907.

s. M. GOPFMA-N. SINGLE EGGBNTRIG REVERSING GEAR FOR STEAM ENGINES.

APPLICATION FILED JULY 11, 1905.

m" m I .36

II V :5 K W 25 30 II. IEHMMI\ 9' inesses: I 71 we 11%;:

UNITED STATES P ifENT oFFioE.

SAMUEL M. GOFFMAN, OF BRAYMER, MISSOURI.

SlNGLE-ECQENTRIC REVERSlNG-GEAR FOR STEAM-ENGINES.

Specification of Letters Patent.

Patented Jan. 22, 1907.

Application filed Julyll, 1905. Serial No. 269.187.

T0 at whom it may concern.-

Be it known that I, SAMUEL M. OoFFMAN,

a citizen of the United States, residing at Braymer, the county ofCaldwell and State of Missouri, have invented certain new and usefulImprovements in Single-Eccentric ReversingGears for Steam-Engines, ofwhich tion of the rod of the eccentric, mounted upon the crank-shaft ofthe engine, in such manner as to dispense with the double eccentric andthe cumbersome link usually employed.

It comprises means for reversing the position of the eccentric-rod whilethe engine is in motion when desired, so as to completely throttle theengine while it is turning in one direction and subsequently to positionthe valve so as to cause the engine to turn in the opposite direction.

With my invention the finest adjustment of the valve from full steam inone direction to full steam in the other is readily and accuratelyattained, and as there "are. no sliding parts the operation of myreversing-gear will be attended with the least possible friction.

In order that the invention may be fully understood, reference will nowbe made to the accompanying drawings, in which Figure 1 represents aperspective view of an engine-frame provided with my improvements. Fig.2 is a vertical section of my improved mechanism, taken on line II II ofFig. 3. Fig. 3 is a plan view of same; and Fig. 4 is a transversesection of the enlarged end of a rocker-shaft employed in carrying p utthe invention, taken on lineIV IV of In said drawings, 1 designates theengineframe. 2 designates a rocker-arm suitably mounted thereon andpivotally connected to the adjacent end of a valve-stem 3 and aconnecting-rod 4. Connecting-rod 4 is pivotally secured at its rear endbetween a pair of aws 5, formed integral with the upper portion of aneccentric-rod 6, extending upwardly from an eccentric-strap 7, the innersurface 8 of which is segmental in cross-section in order to snuglyembrace the crowned periphery 9 of an eccentric 10, rigidly secured upona crankshaft 11 of the engine by means of set-screws 12.

13 designates a pillow-block projecting upwardly from the rear portionof the engineframe and provided at its upper end with a bearing 14 forthe reception of a horizontal rocker-shaft 15, provided at one end witha crank-arm 16 and at its opposite end with an annular shoulder 17,through which a transverse pin 18 extends.

19 designates a yoke consisting of a pair of diver ing arms 20, arrangedon opposite sides of caring 14 and united at their converging ends by aV-shaped portion 21, having an integral centrally-disposed arm 22, ter

minating at its free or swinging end in aball 23. Ball 23 is mounted ina socket 24, arranged in the upper end of the eccentric-rod, and a cap25, which latter is secured to said eccentric-rod with bolts 26 andprovided with an oil-cup 27, communicating at its lower end with theball-and-socket joint, so the same may at all times be kept lubricated.

Pin 18 is held from longitudinal movement by an integral head 28 at oneend and a nut 29 engaging its opposite threaded end 18 said head and nutbearing against the terminals of arms 20 20 gage internal threads in arm20, which cause pin 18 to rock with yoke 19, and all lost motionoccasioned by wear on said pin and its bearings is taken up by a block30 and an adjusting-screw 31. Block 30 is slidingly arranged in theenlarged end of bore 3O" and provided with a semicircular recess 30,which snugly fits the adjacent side of pin 18. Adjusting-screw 31 isprovided at its outer end with a head 32 for the reception of awrench,'whereby said screw is operated. Its inner end bears against theinner end of block 30, thus controlling the pressure of said blockagainst pin 18 and the pressure of the latter against itsbearing-surfaces in shoulder 17.

33 designates a wrist-pin projecting from the lower end of crank-arm 16for the recep- Threads 18 ention of the forward end of a connecting-rod34, pivotally secured at its rear end to a reversing-lever 35, fulcrumedat its lower end. upon a pin 36', projecting from the lower portion of anotched segment 37.

When the engine is running in a' given direction under alight head. ofsteam and it is desired to admit more steam to the cylinder, the valveis moved forwardly by throwing the reversing-lever backwardly until itslatch 38 engages the desired notch in segment 37. This movement of thereversinglever draws the lower end of crank-arm 16 rearwardly, partlyrotating rocker-shaft 15,

which carries yoke 19 therewith. Partial rotation of the yoke adjuststhe upper end of the eccentric-rod forward slightly through theinstrumentality of the ball-and-socket connection to the position shownin Fig. 1. The forward movement of the upper end of the eccentric-rodadvances the valve through the instrumentality of connecting rod 4,rocker-arm 2, and valve-stem 3, so that the ports will be uncovered to agreater extent when the valve reaches the end of a forward stroke. Thedirection of the engine may be readily reversed by throwing thereversinglever forwardlyin the direction of arrow a until latch 38engages one of the forward notches on segment 37, or the engine maybecomletely throttled by moving the reversingever to a vertical position,so that latch 38 will engage central notches 39 of the segment. Afterthe yoke has been adjusted to the desired position it will be reliablyheld from further rotation by latch 38 engaging one of the notches inthe segment, although the ball end of said yoke will be free tooscillate or move up and down with the eccentricrod, the upper end ofwhich latter is permitted to describe the same are as that of the ballend of the yoke through the instrumentality of the crowned periphery 9.Consequently it will be impossible for the ball-andsocket joint tobecome cramped.

From the above description it is apparent that I have produced areversing mechanism which is simple in construction, accurate inoperation, and owing to the absence of sliding parts its operation willbe attended with but little friction or wear.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is

1. In a reversing-gear for engines, the combination with a valvemechanism, of gearing for transmitting motion from the crank-shaft ofthe engine to said valve mechanism, a member for adjusting said gearing,said member being arranged to oscillate on its transverse axis and rockon its longitudinal axis, and means for rocking said member.

2. In a reversing-gear for engines, the combination with a valvemechanism, of gearing actuated by the crank-shaft of the engine andincluding a rod connected to said valve mechanism for operating thesame, a mem ber for adjusting said rod, said member being arranged tooscillate on its transverse axis and rock on its longitudinal axis, andmeans for rocking said member.

3. In a reversing-gear for engines, the combination with a valvemechanism, of gearing actuated by the crank-shaft of the engine andincluding a rod connected to said valve mechanism for operating thesame, a yoke loosely connected at one end to said rod and pivotallymounted at its opposite end, and means for partially rotating said yoke.

4. A reversing-gear for steam-engines consisting of an eccentric havinga crowned pe riphery, an eccentric-strap encircling said eccentric andprovided with an inner surface snugly fitting its crowned periphery, aneccentric-rod secured to the eccentric-strap and the valve mechanism ofthe engine an oscillating member for adjusting the opposite end of saideccentric-rod, and means for controlling the oscillating member.

5. A reversing-gear for steam-engines consisting of an eccentric, aneccentric-rod suitably mounted thereon lor transmitting motion to thevalve mechanism of the engine a yoke pivotall y mounted at one end andloosely connected at its opposite end to the eccentric-rod, and meansfor partially rotating said yoke in either direction.

6. A reversinggear for steam-engines consisting of an eccentric, aneccentric-rod suitably mounted thereon for transmitting motion to thevalve mechanism of the engine an oscillating member jointed at itsswinging end to said eccentric-rod for the purpose of adjusting thesame, arocker-shaft to which said oscillating member is pivotallysecured, and means for partially rotating said rockershai't in eitherdirection.

7. A reversing-gear for steam-engines consisting of an eccentric, aneccentric-rod suitably mounted thereon for transmitting motion to thevalve mechanism of the engine an oscillating member jointed at itsswinging end to said eccentric-rod for the purpose of adjusting thesame, a rocker shaft upon which said oscillating member is pivotallymounted, a crank-arm secured to said rockershaft, and a reversing-leversuitably secured to said crank-arm.

8. A reversing-gear for steam-engines consisting of an eccentric, aneccentric-rod suitably mounted thereon for transmitting mo tion to thevalve mechanism of the engine an oscillating member for adjusting saideccentrio-rod, a rocker-shaft, a shoulder formed integral therewith, atransverse pin extending through said shoulder and carrying theoscillating member, a block slidingly arranged in the rocker-shaft, anadjustingscrew also arranged in said rocker-shaft and adapted. to forcethe block into contact with the transverse pin, and means forcontrolling said rocker-shaft.

9. In a reversing-gear for engines, the combination with a valvemechanism, of gearing actuated by the crank-shaft of the engine andincluding a rod connected to said valve mechanism for operating thesame, an oscillating member for adjusting said rod, a rocker shaft, atransverse pin extending loosely through said rocker-shaft and carryingthe oscillating member, means for taking up lost motion occasioned bywear on said pin and its bearing in the rockershaft, and means foroperating said rocker-shaft.

10. In a reversing-gear for engines, the

com bination with a valve mechanism, of gearing actuated by thecrank-shaft of the engine and including a rod connected to said valvemechanism for operating the same, a member for adjusting said rodand'connected thereto bya ball-and-socket joint, said mem ber beingarranged to oscillate on its transverse axis and rock on itslongitudinal axis, and means for rocking said member.

11. In a reversing-gear for engines, the combination with a valvemechanism, of

gearing for transmitting motion from the crank-shaft of the engine tosaid valve mechanism, a yoke for adjusting said gearing, said 15 yokebeing arranged to oscillate on. its trans verse axis and rock on itslongitudinal axis, and means for rocking said yoke.

In testimony whereof I afiix my signature in the presence of twowitnesses.

SAM [E L M. COFFMAN. Witness es MINNIE ANDRE, IRA JAMES.

